Apparatus for cutting metal along curved lines



-APPARATUS FOR CUTTING METAL ALONG cURvED LINES July 9, 1946. J. F. FRANZEN Filed Sept. 10, 1945 ATTORNEYS s lParitair orrics UNITED STATE APPARATUS FOR CUTTING METAL ALONG CURVED LINES James F. Franzen, Chicago, Ill., asslgnor to Air Reduction Company, Incorporated, a corporation of New York Application September 10, 1943. Serial No. 501,885

4 Claims. (Cl. 266-23) This invention relates to apparatus for cutting.

metal work-pieces by means of gas cutting torches and more particularly to apparatus for cutting a bevelled edge on the work-piece along a curved trolling the motor are shown at 5 and- 6, and the .usual clutch lever at 1.

The carriage has a vertical post 8 to which a f bracket 9 is clamped. The bracket is provided line. y 5 with a sleeve l0 in which a torch arm l l is mount- /It is vcommon practice to cut metal plates and ed. The torch arm projects laterally from the other work-pieces by means of an oxyacetylene carriage and may be adjusted longitudinally of torch mounted on a self-propelled carriage adaptitself in the sleeve it by turning a knob l2 (Figs. ed to run on a track or directly on the work. 1 and 3). A bracket i3 is clamped to the outer According tothe present invention such a torch lo end of the arm ll and has a split sleeve it which carriage is made useful for cutting metal workreceives a stud l5 carried by the torch holder i6 pieces along a curved Aline having a relatively and disposed longitudinally of the carriage. A small radius that producesv a curved corner with gas cutting torch il, such as an oxyacetylene cuta rather abrupt bend. For this purpose certain ting torch of the usual type, is mounted in the additional parts are' attached to the carriage i5 holder'l and may be adjusted vertically therein which cooperate With guiding means along the yby turning the knob i8. The torch holder I6 course of the carriage 'all adapted and arranged may be adjusted about the axis of the' stud i5 to cause movement of the carriage in a predeter-1 and a nut i9 on the split sleeve it enables the mined manner to produce a curved cut of the sleeve to be clamped to the stud to retain the desired type. -The improved apparatus is intended g@ torch holder and the torch in adjusted position. primarily for cutting on a metal work-piece a When the apparatus is used for cutting a bevel y bevelled edge that has a rather abruptly curved on the work-piece the torch holder is adjusted corner` of the kind above referred to and for proabout the aXiS of the Stud l5 S0 that the torch ducing a uniform bevel all along the edge despitel makes the proper angle with the surface of the the curved corner of relatively small radius. gg Work-piece as best shown in Fig. 3.

The invention is illustrated in the accompany- The torch carriage, as well as the torch and the ing drawing in which; means for mounting it on the carriage, as thus Fig. 1 is a plan view of the apparatus; far described, constitute a standard and well Fig. 2 is a side elevation of the apparatus shown known piece of equipment. T0 adapt the Carriage in Fig. 1; 30 for the present purpose, vit has attached to it, on Fig. 3 is a transverse section taken on the linev the tOreh-Side 0f the Carriage. an arm 20 which 3 3 of Fig, 1; extends forwardly as shown.y This arm appears Fig. 4 is a detail view in side elevation showing IlOSUCleally in Fig. 2- It rigidly Carries 'a CrOSS- the guide rollers which engage the outer guide piece 2| (Figs. 3 and 6) on which a pair of rollers rail; 35 22, 23 are mounted by stud screws 2li, 25. An-

Fig. 5 is an end View of the parts shown in Fig. other arm 26 (Fig. 1) is attached to the opposite 4 as viewed fromright to left; and side of the carriage and extends rearwardly. This Fig. 6 is a detail view corresponding to Fig. 5 arm likewise has a cross-piece or roller arm 2l showing the guide rollers which engage the inner (see also Figs. 4 and 5) but in this case it is pivotguide rail. 40 ally supported by the arm 26 by meansof a stud The torch carriage is represented in general at screw 21 (Figs. l and 5). A pair of rollers 28, 29 A. It may be of a well-known type such as that are mounted on the cross-piece 27 by means of disclosed in the patent to J. L. Anderson, No. stud screws 3Q, 3l'aS best Shown in Fig. 5- 2,266,730. It has a pair of forward wheels i and 'I'he carriage runs directly on a plate 32 which 2, and in the present instance, a single rear caster 45 lies over part ofthe work-piece W. In the preswheel 3, although two rear caster wheels may be ent instance the work-piece ls represented as an used if desired, one at each rear corner of the elongated plate Whose portion to be out projects carriage. One of the front wheels is driven by beyond the plate 32, as shown at 33 in Fig. 1. The an electric motor within the carriage (notshown) work-piece may .be supported in any suitable way and the other front wheel ls an idler wheel. The 50 under the plate 32. lThe particular supporting motor is provided with a centrifugal speed conmeans shown in the drawing comprises a pair of trol governor adapted to be adjusted by turning angle irons 34, 35 welded or' otherwise attached the knob 4 so that the carriage may be made to to the under surface of the plate 3? so thattheir move along its course at the desired uniformcuthorizontal flanges 36, 31 form ledges to support ting speed. The usual electric switches for con. u the work-piece when the work-piece is slid longif 3 tudinally into the compartment formed between the angle irons (Fig. 2). If desired suitable means may be employed to clamp the work-piece and hold it firmly in place during the cutting operation. y

Assuming the end of the work-piece is'to be cut along a line which will give it the shape shown in Fig. 1, i. e., withstralght edges at Il and 4l and an intermediate curved corner 42 having a rather small radius, then inner and outer guide rails 43, M having the configuration shown in Fig. 1, are tack-welded to the upper surface of the plate 32 in the positions shown During movement of the torch carriage to cut the workpiece to the shape shown, the rollers 22, 23 on the arm 2U engage opposite vertical faces of the inner guide rail 43 and the rollers 28, 2S on the arm 26 engage opposite vertical faces of the outer guide rail 44. As will be seen from the drawing, the tip of the torch is substantially in transverse alignment with the Contact points of the front carriage wheels, i. e. the points at which they contact with the plate 32, and the rollers 22, 23

vengage the guide rail d3 at a point which is substantially in transverse alignment with the torch tip and the contact points of the front carriage wheels. The rollers 28, 25 engage the outer guide rail 4l at a point off the outer rear corner of the carriage.

To determine the configuration and position of caster the guide rails, the carriage is first moved over the plate 32 manually andthe tip of the torch is made to follow the line along which the proposed cut is to be made in the work-piece. The paths followed by the rollers 22, 23 and 28, 29 are then indicated on the surface of the plate 32 and the guide rails are tack-Welded to the plate accordingly. It will be seen from the drawing that each guide rail has straight end portions corre spending to the straight end portions of the cut to be made in the work-piece, and an intermediate curved portion corresponding to the curved corner to be cut in the work-piece.

If found necessary, a bearing bracket 3l', may

` be attached to each side of the arm 26 near its rear end to constitute a journal mounting for a relatively wide roller 32 adapted to rim on the top edge of the outer guide rail M and thereby support some of the weight of the corner of the carriage to which the arm 26 is attached.

1f desired, and if the nature of the cut to be made in the work-piece requires it, the supporting wheels ofthe carriage could be made to run on a traclrA before and after the carriage is under the influence of the guide rails 43, M However, the portion of the surface of the plate 32 over which the carriage travels While it is passing between the guide rails is trackless and the carriage is then under the iniluence of the guide rails only. Thus the supporting wheels of the carriage move along the surface of the plate 32 in the direction they are caused to move by the guide rails and in the particular fashion which will cause the torch to cut the relatively smallradius' curved corner in the work-piece. The bevel 45 cut on the edge of the work-piece is uniform all along the edge .despite the curved corner.

While the apparatus was intended primarily for cutting bevels along curved lines it may be used, if desired, for cutting along curved lines to produce a vertical-wall cut.

I claim:

1. Apparatus for cutting metal Work-pieces comprising a self-propelled carriage having a `pair of forward wheels and at leastV one rear wheel, a motor for driving one of the forward wheels, a torch arm mounted on the carriageand projecting laterally therefrom, a gas cutting torch carried by said arm. at van angle to the surface of the work-piece whereby the cut made bythe torch produces a. bevel edge on the work-piece, the tip of the torch being substantially in transverse alignment with the contact points of the forward carriage wheels, and means for causing movement of the carriage in a predetermined manner to cause the torch to cut a. bevel edge on the work-piece having a curved corner of relatively small radius whose center is at that side of the carriage where the torch is located, said means comprising a pair of guide rails between which the carriage is adapted to vtravel and portions of which are curved about the center of the curved corner to be cut in the workpiece, an arm attached to that side of the carriage Where the torch is located, a pair of 'rollers carried by said arm engaging opposite vertical faces of the corresponding guide rail and located substantially in alignment with the tip of the torch and the contact points of `the forward carriage wheels, a second arm attached to the opposite side of the carriage .and projecting toward the rear thereof and a pair of rollers carried by *said second arm and engaging opposite vertical faces of the other guide rail.

2. Apparatus for cutting metal work-pieces comprising a movable wheeled torch carriage, a gas cutting torch carriedby the carriage and supported at one side thereof, said torch having its tip directed at an angle to the surface of the work-piece so that the cut made by the torch produces a bevel edge on the work-piece, and means for guiding the carriage during its movement so that the cut made by the torch has a curved corner of relatively small radius convexed toward the carriage and whose center is at that side of the carriage where the torch is located, said means comprising inner and outer guide rails between which the carriage is adapted to travel and portions of which are curved about the center of the curved corner to be cut in the Workpiece, an arm attached to the carriage at the torch side thereof and having a pair` of rollers engaging opposite vertical faces of the inner guide rail, and an arm attached to the opposite side of the carriage and having rollers engaging opposite vertical faces of the outer guide rail.

3. Apparatus for cutting metal work-pieces comprising a movable torch carriage having a pair of forward wheels and at least one rear caster Wheel, a gas cutting torch carried by the carriage and supported at one side thereof, and means forl guiding the carriage during its movementso that the cut made by the torch has a curved corner convexed toward the carriage and whose center is at that side of the carriage where the torch is located, said means comprising inner and outer guide rails between which the carriage isadapted to travel and portions of which are curved about the center of the curved corner to be cut in the work-piece, an arm attached to the torch` side of the carriage, a pair of rollers carried by said arm and engaging opposite vertical faces of the inner guide rail and `located substantially in alignment with the tip of the torch and the contact points of the forward carriage wheels, a second arm attached to the opposite side of the carriage and projecting toward the rear thereof, a roller arm pivoted to said second arm, and a pair of rollers carried by said relatively small radius convexed toward the car- Iringe and whose center is at that side of the car'- riage where the torch is located. said means comrprisms inner and outer guide rails between which the carriage is adapted to travel and portions of which are curved about the center of the curved corner to be cut in the work-piece, an arm at.

tached to the carriage at the torch side thereof and having roller means guided by the inner guide rail, and an arm attached to theopposite side of the carriage and having roller means guided by the outer guide rail.

'JAMES r'. FRANzN. 

